Fluid actuated rotary tool



Dec. 28,. 1943. F. JIMERSON" FLUID ACTUATED ROTARY TbOL Filed Dec. 5, 1941 H is ATTORNEY.

Patented Dec. 28,

* UNIT-ED "STATES PATENT OFFICE.

This invention relates to fluid actuated tools,

and more particularlyto a controlling device for I l a fluid actuated tool-of the portable rotary type;

as for example tapping machines, drills, reaming machines and the like. One object of th invention is to enable the controlling device to be conveniently manipulated with a minimum of eflort.

Another object is to enable the directional. rotation of the rotary parts of the tool to be,

controlled in a simplified and novelmanner.

Other objects will be in part obvious and in part pointed out hereinafter.

II In the drawing accompanying this specifics-J .15 bushing is somewhat enlarged, and at its tion and in which similar reference numerals refer to similar parts;

Figure 1 is a side elevation, partly broken away, of a fluid actuated rotary tool embodying the invention, and I Figures 2, 3 and 4 are transverse views taken 4-4, respectively.

Referring more particularly to the drawing, the

' tool, designated in general by 20, comprises a casing 26 having a laterally extending grip portion 23 near its rearward end and a chuck 23 at its opposite end. y

In the portion of the casing 2! adjacent the grip 22 is a bore 24 having arranged therein a tubular member 25 that serves as a container for a cylinder at and front and rear end heads 21 and 28, respectively. At the rearward end of the tubular member 25 is an introverted flange 29 to serve as aseat for the head 28 and a nut 35 selectively into the chamber 38 on opposite sides 30 is threaded into the opposite end of the tubular member 25 and seats against the head 27 for clamping the heads 21 and 28 and the cylinder inifixed positions within the tubular member 25.

The said heads and cylinder may, if desired,

be additionally secured with respect to each other and with respect to the tubular member by keys or pins (not shown) The interior, of the cylinder 26 serves as a chamber ti and contains a' rotor 32 having trunnions 33 at its ends that extend through.

the heads 2i and 28 into the inner races of anti friction bearings 34 arranged within annular extensions 35 on the outer surfaces of the heads 21 and 28. The front trunnion 33 extendin through the head 2? may be connected, in a well known manner, to transmission means (not shown) within the front part of the casing 2i for rotating, the chuck. The foremost annular extension 38 preferably extends closely adjacent the end surface of a member 38 with inthe casing 2| that engages the rearward end of the tubular member 28. 7 The rotor 22 is actuated-by pressure fluid con- I veyed to the chamber ll through the p mem- 10 ber. 22 which has a supply passage 3i extendin therethrough and a bushing 39 threaded into the outer end of the-supply pass e for connection with a supply conduit (not shown). The portion 40' of the supply passage adjacent the inner end is a beveled seat 4| for a poppet valve 42 that controls the flow of p essure fluid through the supply passage. The v ve 42 has a stem 43 extending upwardly throug the grip member I 20 into a recess 44 in the forward nde of the grip through Figure 1 on the lines 2-2, 3-3 and member. =v

The valve is normally-held upon the seat H by a spring interposed between the valve andthe bushing 3.9, and in the recess it is a rocker '25 48 that is pivotally mounted upon a pin 81 and transversely of the grip member 22 for impart ing movement to the rocker $8 to unseat the valve 42. I

- The rotor 32 'is intended for reverse operation and pressure fluid for actuating it is introduced of and adjacent the point of minimum clearance between the rotor and the wall ofthe chamber 36 through inlet passages ti and 52 in the cylinder 26 and the tubular member 26. Pref- 40, erably the outlet ends of the inlet passages open into enlarged cavities 58 of suitable proportions in the wall of the cylinder 26 to assure the delivery of an ample supply of pressure fluid to the cells 34 between the protruding ends of the vanes slidable radially in the rotor 32.

' In the sides of the cylinder 2t and the tubular I member 25 opposite to the point of minimum clearance between the rotor and the cylinder are exhaust ports 58 through which exhaust to fluid may pass from the chamber ti into an exhaust cham er B1 in the casing 28, and in the wall of the casing 28 are exhaust ports 58 through which exhaust. fluid may pass from the sham I i! to the atmosphere.

, The chamber 31 encircles the tubular member 25 and in the lower part thereof is a boss 59 that defines the outlet opening of the supply passage 38 and has a curved surface 60 to conform with the curvature of theperiphery of the tubularmember for which it may act as :abearing. In the boss 59 and in concentric relationship with the supply passage 38 is a. recess;

! for the accommodation of a packing member 62 that bears against the periphery of-the In the event that it be-lntended to effect reverse operation of the rotor, the tubular mem- 'ber 25 is rotated by means of the knob 69 to bring the inlet passage, 52 into communication with the supply passa'ge iifi' and toplace' the inlet passage 5! into position to communicate with the exhaust chamber 51. The pressure fluid then flowing into the chamber 3i will cause the rotor 32 to rotate in a counterclockwise direction and will exhaust through theexhaust ports 56, the

V exhaust chamber 51 and the exhaust ports 58 to 62 is hollow having an opening 53 therethrough to afford communication between the supply passage 38 and the inlet passages 5i and 52.

In the form of the invention illustrated, the

I direction of rotation of the rotor 32 is controlled by rotating the tubular member 25 to bring one or the other of the inlet passages 51 and 52 into comunication with the supply passage 38. To

- 'tension 35 and the end wall 65 of the casing 2i,

and on'the plate 54 are forwardly extending fingers 66 that liein slots 61 in the introverted flange 29 to effect interlocking engagement between the plate 64 and the tubular member 25. On the opposite side of the plate 64 is a stem 68 that projects through the end wall 65 and car.- ries a knob 59 whereby rotational movement may be manually imparted to the tubular member 25. The knob' is secured fixedly to the stem 68 by a pin extending through the two parts and has a recess ll forthe accommodation of a locking member 12, shown as being in. the form of a ball,'for engagement with a depression, or depressions," in the adjacent surface of the end wall 55. A spring 14 in the bottom of the recess ll constantly maintains the ball 12 in position for engagement with the depressions 19.

The limiting positions rotatively oi the tubular member 25 with respect to thecasing 2| are determined by a' stop device consisting of a pin 15 in the knob 69 and extending into an arcuate slot 16 in the outer surface of the end wall 55, the slot I6 being of such length that when the pin I5 is moved into engagement with an end of the slot 16 an inlet passage, either 5| or 52 deknob 69, will be in full registry with the supply passage 38.

Preferably the grip member 22 is provided with a reservoir 11 for oil that may be introduced into the pressure fluid flowing to the rotor through an oriflce 18 leading from the reservoir to the portion 'of the supply passage 38 lying between the valve seat and the bore 24.

In the operation of the device, and assuming the cylinder assembly to occupy a position in which the inlet passage 5| registers with the suppending upon the direction of rotation of the ply passage 38, as illustrated in Figures 1 and 2 of the drawing, the plunger 5|! is actuated to unseat the valve 42'. Pressure fluid then flows through the supply passage 38 and the inlet passage 5| into the chamber SI for driving the rotor in a clockwise direction a Figure 1- is viewed from the right hand end. The pressure fluid performing this work is exhausted from the chamber 3i through the ports 55 into the chamber 51, thence through the exhaust ports 55 to the atmosphere. Such air as may be present in the cells 54after the vanes 55 have passed the exhaust ports 55 will be carried to the inlet passage 52 and pass therethrough into the eX haust chamber 51,

the atmosphere, and, of course, any air remainingin the cells 54 after the vanes have passed the exhaust ports 56 will flow into the exhaust chamber 51 through the inlet passage 5i.

I claim: -l. A fluid actuated rotary tool, comprising a casing having a supply passage and an atmospheric exhaust passage, a tubular member rotatable in the casing, a cylinder in the tubular member having a chamber, a pair of radially spaced inlet passages in the tubular member and the cylinder opening into the chamber, there being a free exhaust port in the cylinder and the tubular member to communicate the chamber with the exhaust passage, heads in the tubular member for the chamber, means for securing the cylinder and the heads to the tubular member, a rotor arranged eccentrically in the chamber and the point of minimum clearance be-' tween the rotor and the cylinder being diametrically opposite the exhaust port, and means for rotating the cylinder to different positions within the casingto selectively bring either inlet passage into communication with the supply passage for causing the rotor to turn in one direction or the other and to simultaneously bring the other inlet passage into communication with the exhaust passage to afford an additional outlet for the escape of fluid from the chamber.

2. A fluid actuated rotary tool, comprising a casing having a bore and an exhaust chamber intermediate the ends of the bore, a free atmospheric exhaust port in the casing for the exhaust chamber, a supply passage in the casing open ing intothe bore in the transverse plane of the "exhaust chamber, a tubular member rotatable in the bore extending through the exhaust chamber, a cylinder in the tubular member having a rotor chamber, a free exhaust port in the cylinder and the tubular member to afiord communication between the rotor chamber and the exhaust chamber, heads in the tubular member for the rotor chamber, means for securing the cylinder and the heads to thetubular member, a rotor arranged eccentri'cally within the rotor chamber and the point of minimum clearance 1 cylinder to diflerent positions within the casing to selectively bring eitherinlet passage into registry with the supply passage for causing the rotor to turn in one direction or the other and to simultaneously bring the other inlet passage intocommunication with the exhaust passage to vent the cells after the said .cells have passed across the exhaust port for the rotor chamber.

., FRANCIS A. JIMERSON. 

